Method of treating motion picture films



March 3, 1942. G. J. GAGE I METHOD OF TREATING MOTION PICTURE FILMS Filed April 9, 1958 5 Sheets-Sheet l NTOR i l/ w ATTORNEY March 3, 1942.

G. J. GAGE METHOD OF TREATING MOTION PICTURE FILMS Filed April 9, 1938 5 Sheets-Sheet 2 C eo INVENTOR BY rge TGaye ATTORZTIE Y March 3, 1942. G, J GAGE 2,275,139

METHOD OF TREATING MOTION PICTURE FILMS Filed April 9, 1958 5 Sheets-Sheet 5 ENTOR f g o/ye f a e IT kim- March 3, 1942. G. J. GAGE 2,275,139

METHOD OF TREATING MOTION PICTURE FILMS Filed April 9, 1958 5 Sheets-Sheet 4 INVENTOR (1 5C196 IGage 2 ars. IM.

ATTORNEY March 3, 1942. J GAGE I 2,275,139

METHOD OF TREATING MOTION PICTURE FILMS Filed April 9, 1958 5 Sheets-Sheet 5 I NV EN TOR Geo *9? I Gay 6 Patented Mar. 3, 1942 UNITED STATES PATENT OFFICE METHOD OF TREATING MOTION PICTURE FILMS 1 Claim.

This invention relates to the method of treating motion picture film and is an improvement upon the invention disclosed and broadly claimed in United States Letters Patent No. 2,011,576, issued to me August 20, 1935.

My invention is primarily directed to an improved method enabling all and singular the various steps in the method set forth in my aforementioned letters patent to be practiced with greater precision and speed and accompanying attainment of certain new and highly advantageous results.

My prior patent teaches that by simultaneously applying heat and surface pressure to the film to slightly soften the emulsion the silver deposit on the emulsion is effectively flattened and the infinitesimal voids in the surface of the emulsion closed so as to prevent carbonized matter from settling therein and also, greatly to minimize friction on the film when pulling the film through a projector.

It is my opinion that motion picture film is affected by certain climatic (particularly arid), conditions, and also by radiant heat from the arc in the optical system of a motion picture projector to the extent that deterioration of the film results which is proportional to the rate of loss (by evaporation) of the moisture content from the molecular structure of the film. In consequence thereof, the film loses its vitality, softness, pliability and other characteristic qualities so necessary for continued practical use of the film. I find this true of both old and new film and also of film that has merely remained in storage and has never been exhibited.

I have discovered that by occasionally replenishing the molecular structure of the film with moisture, all of the characteristics favorable to practical usage of the film are retained and the structure placed in a soft, pliable condition.

It is a matter of common knowledge that, in general, bodies increase in size as the temperature increases. I further have discovered that when a motion picture film is run through a picture projector, heat from the projectors arc strikes or attacks the longitudinal center of the film with greater severity at the center than at the longitudinal edges of the film and that there is elongation linearly and medially of the film which is not proportional to that occurring at u said longitudinal edges. This causes buckling of the film and tends to destroy necessary horizontal alignment of the sprocket openings, such that when the film is again run through the projector,

said openings do not correctly intermesh with the teeth of the driven sprockets. This, sooner or later strains the walls of the openings and tears and breaks down the edges of said film. In addition to this impairment, the frames of the film no longer register exactly as intended with the frame aperture of the projector, and in addition thereto, the intended order of the sound recordings relative to the pick-up mechanism of the sound reproducing apparatus is materially interfered with, making impossible faithful repro duction of sound.

I find that if the film while in continuous translation is subjected to the effect of a humidifying medium at film contracting temperature and substantially concurrently therewith is subjected to the effect of correct surface pressure and heat, the temperature of which is high relative to that of the humidifying medium, normal shrinkage is secured and that if the surface pressure is applied by surface pressure media which seals the film therebetween, essential portions of moisture are transmitted to the molecular structure of the film. If old film is treated in the manner aforestated and is also correctly subjected to the effect of dirt, grease and discoloration eliminating and also to stain neutralizing agents, it can be restored to a. condition which is comparable to fresh soft film that has never been run through a projector.

It is of course understood that a film once treated as aforestated, should, for continued preservation thereof be similarly treated from time to time.

The present invention changes somewhat the modus operandi of my prior patented method, and has for some of its more important features, those, as follows, to wit:

(l) The feature enabling film to be conditioned at low cost and in a manner to insure beneficial results.

(2) The feature enabling the film to be treated more thoroughly while in continuous translation.

(3) The feature which insures a highly effective scrubbing of the film with a cleaning agent and effective removal from the film of all dirty I fluid and loose particles of foreign matter before the film is subjected to final treatment.

(4) The feature which insures translation of the film through the heat zone at a speed which exactly corresponds with the angular velocity of the surface pressure media.

(5) The feature which substantially seals the film between the surface pressure media, to thereby insure transmission of moisture to the molecular structure of the film during the step of raising the temperature of the film.

(6) The feature enabling the amount of pressure of the surface pressure media accurately to be controlled.

(7) The feature which insures rapid translation of the film in operative synchronism with all other operations.

(8) The feature making possible controlled transmission of the film at desired speed.

(9) The feature enabling a discoloration correcting and stain neutralizing agent pneumatically to be applied at any pressure deemed by the operator to be best suited to conditions and to place the film at a temperature to insure beneficial treatment thereof when subjected to the surface pressure media and heat.

(10) The step in the method which insures giving to the film the property more readily to transmit light with resulting increased clarity of the projected images.

(11) The feature enabling satisfactory correction of the aforestated inequalities and heretofore existing imperfections and in addition thereto insures better definition of the sound track.

(12) The feature which insures absolute cleanliness of the film before receiving a light rectifying treatment.

(13) The feature enabling controlled portions of the rectifying solution to be applied to the film and uniformly distributed throughout all surfaces thereof.

Wherever herein the invention is said to reside in a theory, it shall be clearly understood that I am not to be bound to the correctness thereof. Actual practice, however, and careful comparison of relative results, seem clearly to show that the theory as stated is correct.

Other objects and advantages will appear in the following specification, and the novel features of the-invention particularly pointed out in the appended claim.

My invention is illustrated in the accompanying drawings forming a part of this application, in which Figure 1 is a front elevation of the mechanism with parts broken away and parts in section;

Figure 2 is a view in rear elevation of the mechanism;

Figure 3 is a vertical section on an enlarged scale taken substantially on the line 3-3 of Figure 1;

Figure 4 is a horizontal section taken substantially on the line 44 of Figure 1;

Figure 5 is a vertical section taken on line 5-5 of Figure 2;

Figures 6, 7, 8 and 9 are respectively detail sections taken on the lines 66, 1'l, 8--8 and 99 of Figure 1;

Figure 10 is a section taken on line ll0 of Figure '7;

Figure 11 is a section taken on line H-l| of Figure 8; and

Figure 12 is a schematic illustration partly in elevation and partly in section of the heating and pressing means.

In carrying the invention into practice use is made of mechanism providing zones 500 and 600. Continuous reeling and unreeling of the film while undergoing treatment in these zones is accomplished by means of a pay-off reel 300 and a take-up or winding reel 490.

The zone includes a lower pair of horizontally aligned nozzles l5-l5; an upper pair of horizontally disposed nozzles l6-l6 and an in termediate pair of horizontally aligned nozzles l1ll. All of these nozzles are suitably supported by a vertical panel I 8 which rises from an understructure 19, the latter accommodating air compressor 20 and a motor 2|.

The nozzles of each of the aforestated pairs are situated with respect to each other to provide a space between the discharge orifices thereof through which the film can pass without any possibility of its contacting said nozzles. The arrangement also is such that a blast of fluid under pressure will be effectively discharged against an adjacent side of the film from the orifices of each said nozzle.

It is intended that from the intermediate nozzles ll clean air shall discharge against opposite sides of the film at approximately thirtyfive pounds pressure.

From the upper nozzles it it is intended that a mixture comprising carbon tetrachloride and chloroform or their equivalents, also Victoria blue or its equivalent shall discharge against opposite sides of the film at a pressure of approximately thirty-five pounds.

From the lower nozzles l5 it is proposed to discharge cleaning fiuid against opposite sides of the film at a pressure of from 1 to 5 pounds. This fiuid may comprise carbon tetrachloride with a suitable portion of chloroform, the latter being a solvent, serving to slightly soften the Celluloid side of the film so that when surface pressure and heat are applied to the film, all surface scratches in said Celluloid side of the film will be effectively closed.

The speed of the film during reeling and unreeling thereof should be constant and equal in every respect to the angular velocities of the surface pressure media at the zone 600. A satisfactory practical speed is estimated between the range of from to feet per minute.

In the zone 600 is a rotary drum-like heater 22 of substantial diameter, provided with a perfectly smooth periphery 23, the face width of which is approximately the same as the width of the film. Said drum is provided with parallel spaced apart side fianges 24 for confining the film against lateral displacement during continuous translation of the film. The hub 25 of the drum is freely supported upon a spindle 26 which projects horizontally from the front of the panel l8. As this drum is very similar structurally and functionally to the drum I in my aforestated prior patent, it will suflice to say that it is hollow and contains a resistance coil adapted when in closed circuit with a source of electrical potential to heat the drum to desired temperature. A practical temperature for my purpose is approximately F.

The drum 22 in addition to being employedas a heat conductor also is an element in a combination of various means providing surface pressure media for gripping and evenly pressing the film 1.00 almost concurrently with departure thereof from zone 500.

In the general scheme of things, an endless pressure belt 21 is trained over a pulley 2B and has leads 29-29, constricted relatively in a downward direction by their passage between horizontally aligned pulleys 30-40, the belt then passing snugly around drum 22. A similar but somewhat longer belt 31 comes snugly next to the belt 21 and is trained over the pulleys 3030, across pulleys 32-32, thence under pulley 33. The belts 2'1 and 3| are preferably constructed of the same material as the film 100. That is to say, they can be formed of raw film stock. A third belt 34 is employed and is preferably made of one piece woven fabric, stitched, as is customary to render it as nearly unstretchable as possible. It is trained over the pulleys 39 and comes under belt 3| circumferentially of the drum 22 and passes over pulleys 32, 32, thence under pulley 35. The training of this belt is such that its wrap 334 is outermost of similar wraps of belts 21 and 3|.

The pulley can move vertically in order that by the means presently to be described it can be raised and lowered to enable the tension on the belt 34 to be controlled, whereby the amount of surface pressure imposed upon both sides of the film 103 can be regulated to a nicety.

By reason of the arrangement of said belts 21, 3| and 34, film can be threaded into the space between belts 21 and 3| from point 36 at the left of Fig. 12, and after being acted upon by the combined belts and the drum 22 can leave from the exit 31 to be wound upon reel 490. The film 100 is thus always disposed fiatwise between the Celluloid belts 21 and 3| and is positively made to travel in absolute synchronism therewith and with the drum 22.

Pulley 35 has its shaft 38 journaled in a bearing 39, the latter forming a fixed part of a plate 40, movable vertically in guide rails 4| on the panel I8, 43 on said panel and forwardly of the latter, said shaft has a crank arm 44 adapted to be actuated manually and thereby impart vertical motion to said plate 48 through crank arm 45 on said shaft 42 and a coil spring 46, the latter connecting said arm 45 with the aforestated bearing 39. The crank arm 44 has a toothed latching bar 41 which extends through an opening 48 in the top wall of said understructure l9 and is adapted to engage an edge wall of said opening to thereby latch the arm 44 in any position of vertical adjustment.

On the shaft 42 is an idler 49 and trained thereover and around the pulley 50 on shaft 5| of reel 48!), thence around driven pulley 52 on shaft 53' is a driven belt 54. th motor 2| as shown in Fig. 1. It therefore follows that when the motor 2| is operating, power is transferred to the belt 54 thereby driving the reel 409 and simultaneously therewith, power is transferred to belt 34. By reason of intimacy of relationship of the wraps of belts 21, 3| and 34 to each other and to the drum 23, all of said belts and the drum will be driven at the same angular velocities. It manifestly follows also that the linear velocity of the film will be the same as said angular velocities of said belts as it must be if these several instrumentalities are to function in the manner intended.

In order that the belt 21 can also be tensioned, the shaft 51 of pulley 28 is carried by a vertically movable plate 58 mounted in guide rails 59 on the panel l8. A stud 60 extends laterally from said plate and same passes through the eye 6| of an adjusting screw 62. The screw passes through a bracket 63 in back of said panel and is provided with a nut 64 by which the screw can be adjusted and the traveling plate 58 made to ten sion said belt 21 by a change in the elevation of said pulley 28.

The pulley 33 under which the belt 3| passes is yieldingly urged downward by a spring 65 and by this simple means, said belt is under constant resilient tension.

The shaft 5| of reel 400 has a friction element 55 which is yieldingly advanced against a flat A rocker shaft 42 is journaled in a bearing The shaft 53 is belted to face of pulley 50 by a coil spring 56, thereby exerting suflicient drag on the rotation of said reel to prevent it overrunning at the usual operating speeds of th machine.

The nozzles |5-|5 are each provided with orifices 65, the axes of which are parallel to each other and disposed at such angle to the plane of movement of the film 100 as to insure discharge of liquid jets across the surfaces of the film towards a waste collector 66 in front of panel l8. Liquid under pressure is conducted to said nozzles through tubing 61 from a liquid container 68. The container is supplied with liquid from a reservoir 69 through a conduit 10 having a regulating valve 1| and a check valve 12. Air under pressure is supplied the container through tubing 13 from a pressure line 14, the latter provided with a regulator 15 and a pressure gauge 15. In the tubing 13 is a valve 11 for controlling admission of air under pressure to said container 68. Liquid from the container is delivered to the tubing 61 through a valved discharge tube 18 which makes connection with said tubing at the unions 19, the latter having connection with the tubing 61.

The nozzles l1 have their orifices disposed at an angle to insure delivery of fine jets of air against and across the film toward the collector 8. The cleaning liquid used at the nozzles I5 is volatile and when impinged against the surfaces of the film as heretofore described, all dirt, grease and other particles of foreign matter will be rapidly expelled and conducted to said collector. It is intended that all surplus liquid shall be eliminated from the film before the latter passes the nozzles l1. Air discharging from the nozzles |1 insures quick evaporation of the lighter portions of said surplus liquid and in spite of the speed atwhich the film travels, all heavy surplus liquid and loose particles of foreign matter are completely eliminated from the film and the latter placed in a dry clean. condition, ready for the next step in the method of treating same.

Air from the branch pressure line 89 is conducted to the tubing 8| through a conduit 82, the latter having a regulating valve 83.

The container 8| receives its supply of rectifying and lubricating liquid from a reservoir 84 through a conduit 65, the latter having a regulating valve 85 and a check valve 81. Liquid from this container is conducted to the unions 88 through tubes 89 and to said unions run tubes 99 from the branch pressure line through a valved connection 9|. From the unions 88, liquid under pressure is conducted to the nozzles I6 through tubes 92. The orifices of the nozzles l6 deliver a wide fan-shaped spray of liquid across the entire surfaces of th film such as insures covering all parts thereof.

Compressed air is supplied the main line 14 through a conduit 92.

The chloroform used at the nozzles l6 functions to hold the light rectifying agent in solution whereby to insure even distribution of said agent throughout all parts of the print. The Victoria blue used herein as a rectifying agent has desirable lubricating qualities and when the carbon tetrachloride and the chloroform evaporate from the print, the lubricant content of said agent remains and insures smooth running. of the film through the projector without objectionable use of wax at the sprockets.

As the volume of the chemicals discharging from th fluid nozzles in zone 500 can be regulated as desired, it manifestly follows that the temperature of the film can readily be controlled to effect normal shrinkage of the film. As the zones 5G9 and 800 are very closely related to each other normal shrinkage temperature of the film is effectively maintained until the film is securely caught between the surface pressure media in zone 560 where it concurrently is acted upon by the radiant heat of the drum 22 and normal shrinkag of the film very definitely secured, during which time, the film is securely held at all places against movement relative to the surface pressure media.

To the best of my knowledge, the feature which consists in first lowering the temperature to effect normal shrinkage of the film, then setting the film or securing permanent normal shrinkage, is broadly new, and I shall hope to take full benefit of any functional equivalents of the means disclosed herein for accomplishing this rethe film at each pair of nozzles in zone 590 insures definitely isolating the film from said nozzles.

I find also that because of the angle at which fiuid under pressure discharges from the nozzles in zone 586 there is effective turbulence of the fluid which greatly accelerates the effect of the fiuid on the film.

Th term rectifying agent employed herein shall include any chemical or any combination of chemicals capable of neutralizing the effect of the yellowish light obscuring tarnish which the film takes on with age or which comes in consequence of the generation of sulphur fumes either at the arc of the projector during passage of the film across the light or during the process of developing the film.

Th temperatures at the nozzles l5--l5 and [5-16 are maintained between 28 and 30 degrees F. Due to the close proximity of the zone 508 to the heat and pressure zone 600 the film enters the said heat and pressure zone at from 28 to degrees F. It is important to bear in mind that as a result of the temperature of the film relative to the temperature at said heat and pressure zone, humidity is generated between belts 21 and 3| and is eifectively driven into the emulsion and into the Celluloid of the film, thereby supplying the same with moisture necessary for practical preservation of the film during ordinary usage thereof. This treatment is found also to give to the film a highly desirable degree of toughness such as insures against premature damage thereof at the sprocket openings.

At the front of panel I8 switch Hill is employed by means of which the circuit in which motor 2| is connected can be controlled. A similar switch 2911 enables the resistance coil in drum 22 to be placed in either closed or open circuit as required. At 30! is disclosed a moisture condenser which is connected between the air hose 350 and line 14. A thermostat 315 is operatively connected in the circuit of the resistance coil of said drum 22, whereby the temperature of the drum can be regulated to from to degrees F.

What I claim as my invention is:

The herein described method of cleaning and revitalizing motion picture film which comprises continuously moving the film at a predetermined constant linear velocity; pneumatically impinging an atomized liquid solvent against the opposite sides of the film at an angle to direct the liquid across the film and at a controlled velocity to cause dislodgement of foreign matter from said sides to effect discharge of said matter and surplus liquid from said film at one edge of the latter; similarly impinging clean air against said opposite sides of the film to discharge any loose foreign matter remaining thereon and to dry said opposite sides of the film; uniformly wetting said dry sides of the film with a light rectifying and film softening liquid and applying controlled surface pressure and heat to said wet sides of said film.

GEORGE J. GAGE. 

